For examining a patient via an imaging apparatus, a position of a region of interest of the patient relative to an examination unit of the imaging apparatus is typically determined and/or adjusted. For this purpose the patient can, for example, be positioned relative to the examination unit such that a selected slice of the region of interest lies in an examination plane assignable, in particular assigned, to the examination unit. On the basis of such a position of the region of interest, a topogram and/or a conventional radiographic image, for example, can be obtained for planning the acquisition of an imaging data set.
The examination plane can be visually indicated e.g. via a laser localizer. By way of a patient positioning device, the patient can be transferred such that the selected slice comes to lie in the examination plane. For this purpose, an operator can view a position of the selected slice relative to the visually indicated examination plane and adjust the transfer of the patient accordingly. The selected slice can be in particular a slice with which the taking of the topogram and/or the acquisition of the imaging data set begins. The selected slice can be in particular a slice which delimits the region of interest in respect of a scanning direction in which the patient is moved during the taking of the topogram and/or acquisition of the imaging data set. The extent of the region of interest along the scanning direction can be adjusted e.g. by numerical input and/or selection of a length via a user interface.
For taking the topogram and acquiring the imaging data set, the region of interest is typically disposed in an acquisition area of the imaging apparatus, wherein the acquisition area is constituted by a tunnel-shaped aperture and the examination plane runs through the acquisition area. Viewing the position of the selected slice relative to the visually indicated examination plane can be awkward for the operator. Particularly if the selected slice is close to or in the examination plane, it may be necessary for the operator to lean into the tunnel in order to be able to identify the position of the selected slice.